This invention relates to hand tools for turning threaded fasteners, and more particularly to a box wrench for engaging and turning hexagonal nuts and bolts in motor vehicle areas that are ordinarily inaccessible without removing overlying elements such as air conditioning compressors. U.S. Pat. No. 5,230,263 issued Jul. 27, 1993 to Kwaka discusses and reviews the prior art of wrenches and discloses a new wrench that would not resolve the problems the instant invention is intended to overcome. There are certain motor vehicles in which the engine compartment is so crowded with components that access to other elements that must be replaced can only be achieved by first removing the overlying components.
This is the situation that confronts the mechanic who must replace the engine mounts in certain vehicles such as: the front wheel drive Cadillac V8-273-4.5L and the Cadillac Seville 1986 V8-252-4.1L. One of the engine mounts is beneath the air conditioning compressor. In order to remove and replace a defective engine mount, the hexagonal 15 mm nut that secures the upstanding engine mount stud to a bracket bolted onto the engine must be removed. The recommended procedure is quite elaborate, an is estimated by the manual to require 3.1 hours of labor. It involves discharging and removing an overlying air conditioner compressor, removing ground cable, serpentine belt, shields, and removing the bracket from the engine. The engine is then raised and the mount can be unbolted from the frame and removed with the bracket. The bracket is then removed from the mount by removing the hexagonal nut from the stud and a new mount is bolted to the bracket and the entire process reversed. Not only does this take long time, but there is always the possibility of causing damage to any one of the various elements that have been disturbed in the process, and they must also be tested.
If the nut could be removed from stud without disturbing the other components in the engine compartment, the time required to remove and replace the engine mount could be greatly reduced, and inadvertent damage to other components avoided.